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311.
Melanie Hebe Hughes Héctor Juan Prado María Cecilia Rodríguez Karina Michetti Patricia Inés Leonardi María Cristina Matulewicz 《Marine biotechnology (New York, N.Y.)》2018,20(6):706-717
The aims of the present study were to characterize for the first time the carrageenan extracted from cystocarpic stage of S. crispata collected in the Patagonian coast of Argentina, and to prepare interpolyelectrolytic complexes (IPECs) between the polysaccharide extracted from cystocarpic stage of Sarcothalia crispata and Gigartina skottsbergii thalli, and basic butylated methacrylate copolymer (Eudragit E), in order to test their potential for the controlled release of ibuprofen as model drug. The structural determination revealed that the polysaccharides extracted from S. crispata and G. skottsbergii were mainly constituted by κ-carrageenan, particularly in the case of G. skottsbergii; however, significant amounts of ι- and ν-carrageenan were also detected in both polygalactans. The differences in diad composition and possibly in their distribution along the polysaccharide chain of both carrageenans would favor a different arrangement in the resulting IPEC structure. The smaller pores observed by scanning electron microscopy in the IPEC of S. crispata suggest that the kinks in the polysaccharide backbone are evenly distributed, resulting in a slower ibuprofen release compared to the IPEC of G. skottsbergii. 相似文献
312.
Serrano-Sánchez JA Delgado-Guerra S Olmedillas H Guadalupe-Grau A Arteaga-Ortiz R Sanchis-Moysi J Dorado C Calbet JA 《PloS one》2010,5(10):e13435
Background
To determine if there is an association between physical activity assessed by the short version of the International Physical Activity Questionnaire (IPAQ) and cardiorespiratory and muscular fitness.Methodology/Principal Findings
One hundred and eighty-two young males (age range: 20–55 years) completed the short form of the IPAQ to assess physical activity. Body composition (dual-energy X-Ray absorptiometry), muscular fitness (static and dynamic muscle force and power, vertical jump height, running speed [30 m sprint], anaerobic capacity [300 m running test]) and cardiorespiratory fitness (estimated VO2max: 20 m shuttle run test) were also determined in all subjects.Activity-related energy expenditure of moderate and vigorous intensity (EEPAmoderate and EEPAvigorous, respectively) was inversely associated with indices of adiposity (r = −0.21 to −0.37, P<0.05). Cardiorespiratory fitness (VO2max) was positively associated with LogEEPAmoderate (r = 0.26, P<0.05) and LogEEPAvigorous (r = 0.27). However, no association between VO2max with LogEEPAmoderate, LogEPPAvigorous and LogEEPAtotal was observed after adjusting for the percentage of body fat. Multiple stepwise regression analysis to predict VO2max from LogEEPAwalking, LogEEPAmoderate, LogEEPAvigorous, LogEEPAtotal, age and percentage of body fat (%fat) showed that the %fat alone explained 62% of the variance in VO2max and that the age added another 10%, while the other variables did not add predictive value to the model [VO2max = 129.6−(25.1× Log %fat) − (34.0× Log age); SEE: 4.3 ml.kg−1. min−1; R2 = 0.72 (P<0.05)]. No positive association between muscular fitness-related variables and physical activity was observed, even after adjusting for body fat or body fat and age.Conclusions/Significance
Adiposity and age are the strongest predictors of VO2max in healthy men. The energy expended in moderate and vigorous physical activities is inversely associated with adiposity. Muscular fitness does not appear to be associated with physical activity as assessed by the IPAQ. 相似文献313.
Changes in the redox state of the intracellular ryanodine receptor/Ca2+ release channels of skeletal and cardiac muscle or brain cortex neurons affect their activity. In particular, agents that oxidize or alkylate free SH residues of the channel protein strongly enhance Ca(2+)-induced Ca2+ release, whereas reducing agents have the opposite effects. We will discuss here how modifications of highly reactive cysteine residues by endogenous redox agents or cellular redox state influence RyR channel activation by Ca2+ and ATP or inhibition by Mg2+. Possible physiological and pathological implications of these results on cellular Ca2+ signaling will be addressed as well. 相似文献
314.
Slinde F Suber C Suber L Edwén CE Svantesson U 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(2):640-644
In studies of physical performance comprising muscle strength and power, a vertical jump is a test method that frequently is used. It is important to have access to accurate measuring tools providing data with high reproducibility. Studies have shown that body composition also may play an important part in physical performance. The purpose of this study was to determine test-retest reliability for 3 different kinds of vertical jumps and to correlate jump height with body composition. Thirty-four normally trained subjects (women n = 17) between 18 and 25 years participated. Test-retest, on 3 kinds of vertical jumps, was performed with a median of 7 days between jumps. Methods used were a countermovement jump (CMJ) on a contact mat, with and without arm swing, and an Abalakow jump (AJ) using measuring tape, with arm swing. Body composition was assessed with the use of bioelectric impedance analysis. The results showed that high intraclass correlation coefficients (ICCs) were observed between testing occasions for all 3 vertical jumps (ICC between 0.48 and 0.88). The AJ in women presented the lowest ICC. Also the correlation between CMJ and AJ was high (rs = 0.88). Moderate-to-high correlations could be shown between body composition and CMJ in women (rs = -0.57-0.76). In conclusion, very high test-retest reliability for CMJ on a contact mat was found. For the AJ using a measuring tape, ICC were overall high, but a moderate nonsignificant ICC were found in women, indicating poor reproducibility. The data from the CMJ and AJ may be compared if approximately 25% of the AJ value is subtracted. In practice, this means that vertical jump tests have high reproducibility and can be used as measures of power development. 相似文献
315.
Jordi Valls-Margarit Ivn Galvn-Femenía Daniel Matías-Snchez Natalia Blay Montserrat Puiggrs Anna Carreras Cecilia Salvoro Beatriz Corts Ramon Amela Xavier Farre Jon Lerga-Jaso Marta Puig Jose
Francisco Snchez-Herrero Victor Moreno Manuel Perucho Lauro Sumoy Lluís Armengol Olivier Delaneau Mario Cceres Rafael de
Cid David Torrents 《Nucleic acids research》2022,50(5):2464
The combined analysis of haplotype panels with phenotype clinical cohorts is a common approach to explore the genetic architecture of human diseases. However, genetic studies are mainly based on single nucleotide variants (SNVs) and small insertions and deletions (indels). Here, we contribute to fill this gap by generating a dense haplotype map focused on the identification, characterization, and phasing of structural variants (SVs). By integrating multiple variant identification methods and Logistic Regression Models (LRMs), we present a catalogue of 35 431 441 variants, including 89 178 SVs (≥50 bp), 30 325 064 SNVs and 5 017 199 indels, across 785 Illumina high coverage (30x) whole-genomes from the Iberian GCAT Cohort, containing a median of 3.52M SNVs, 606 336 indels and 6393 SVs per individual. The haplotype panel is able to impute up to 14 360 728 SNVs/indels and 23 179 SVs, showing a 2.7-fold increase for SVs compared with available genetic variation panels. The value of this panel for SVs analysis is shown through an imputed rare Alu element located in a new locus associated with Mononeuritis of lower limb, a rare neuromuscular disease. This study represents the first deep characterization of genetic variation within the Iberian population and the first operational haplotype panel to systematically include the SVs into genome-wide genetic studies. 相似文献
316.
Valentina Vernocchi Maria Giorgia Morselli Sara Varesi Simona Nonnis Elisa Maffioli Armando Negri Gabriella Tedeschi Gaia Cecilia Luvoni 《Theriogenology》2014
Ubiquitin is a 8.5-kDa peptide that tags other proteins for proteasomal degradation. It has been proposed that ubiquitination might be responsible for the elimination of defective spermatozoa during transit through the epididymis in humans and cattle, but its exact biological function in seminal plasma has not yet been clarified. In the domestic cat (Felis catus), the percentage of immature, unviable, and abnormal spermatozoa decreases during the epididymal transit, indicating the existence of a mechanism that removes defective spermatozoa. Magnetic cell separation techniques, based on the use of magnetic beads coated with anti-ubiquitin antibodies, may allow the selective capture of ubiquitinated spermatozoa from semen, thus contributing to the identification of a potential correlation between semen quality and ubiquitination process. Moreover, the selective identification of all the ubiquitinated proteins in different epididymal regions could give a better understanding of the ubiquitin role in feline sperm maturation. The aims of this study were as follows: (1) to verify the possibility of separating ubiquitinated spermatozoa with magnetic ubiquitin beads and identify the morphological and acrosomal differences between whole sample and unbound gametes, (2) to characterize all the ubiquitinated proteins in spermatozoa retrieved in the three epididymal regions by a proteomic approach. The data indicated the presence of ubiquitinated proteins in cat epididymal semen. However, a correlation between abnormal and ubiquitinated spermatozoa has not been found, and ubiquitin cannot be considered as a biomarker of quality of epididymal feline spermatozoa. To the author's knowledge, this is the first identification of all the ubiquitinated proteins of cat spermatozoa collected from different epididymal regions. The proteomic pattern allows a further characterization of cat epididymal semen and represents a contribute to a better understanding of the ubiquitin role in feline sperm maturation. 相似文献
317.
Kenneth H. Astrin Cecilia A. Warner Han-Wook Yoo Paul J. Goodfellow Shih-Feng Tsai Robert J. Desnick 《Human genetics》1991,87(1):18-22
Summary Uroporphyrinogen III synthase [UROS; hydroxymethylbilane hydro-lyase (cyclizing), EC 4.2.1.75] is the fourth enzyme in the human heme biosynthetic pathway. The recent isolation of the cDNA encoding human UROS facilitated its chromosomal localization. Human UROS sequences were specifically amplified by the polymerase chain reaction (PCR) from genomic DNA of two independent panels of human-rodent somatic cell hybrids. There was 100% concordance for the presence of the human UROS PCR product and human chromosome 10. For each of the other chromosomes, there was 19%–53% discordance with human UROS. The chromosomal assignment was confirmed by Southern hybridization analysis of DNA from somatic cell hybrids with the full-length UROS cDNA. Using human-rodent hybrids containing different portions of human chromosome 10, we assigned the UROS gene to the region 10q25.2 q26.3. 相似文献
318.
This report is of a round-table discussion held in Cardiff in September 2009 for Cesagen, a research centre within the Genomics Network of the UK??s Economic and Social Research Council. The meeting was arranged to explore ideas as to the likely future course of human genomics. The achievements of genomics research were reviewed, and the likely constraints on the pace of future progress were explored. New knowledge is transforming biology and our understanding of evolution and human disease. The difficulties we face now concern the interpretation rather than the generation of new sequence data. Our understanding of gene-environment interaction is held back by our current primitive tools for measuring environmental factors, and in addition, there may be fundamental constraints on what can be known about these complex interactions. 相似文献
319.
320.
Abstract The content of polyamines and RNA in isolated embryos from dry resting seeds of durum wheat has been determined. This, with the aim to investigate the variations of the polyamines and RNA amounts during the ageing process and to correlate them with the loss of germination capacity of the seeds. The results showed that the total polyamines increase while the RNA content decreases during the ageing of the embryos. Since no great difference exists as to the polyamine content between the embryos from seeds capable and incapable to germinate, it appears to be lacking a close relationship between the polyamine content and the germination capacity of the examined seeds. The decrease of the RNA content and the corresponding increase of the polyamine-N/RNA-nucleotide ratio, seem to suggest that the loss of germination capacity of the wheat seed could be related to impaired regulation properties during the ageing process. 相似文献